Exemplary embodiments of the present invention relate to projectors to project color images using liquid-crystal panels or other light-modulating elements.
The related art includes an optical system included in a typical projector that has illumination-light components of multiple colors emitted towards liquid-crystal display panels where the illumination-light components are modulated. The modulated-light components of the multiple colors are then synthesized in a light-synthesizing member known as a cross dichroic prism, so that a color image can be projected.
Related art document Japanese Unexamined Patent Application Publication No. 2000-206450 includes a projection display device that can correct for chromatic aberrations between colors for proper image formation. In such a projection display device, for example, a red-light incident surface of a cross dichroic prism is made concave and a blue-light incident surface of the cross dichroic prism is made convex. Related art document Japanese Unexamined Patent Application Publication No. 2002-6298 discloses another type that can reduce or prevent displacement of color image components by integrally providing a correction lens composed of resin in one of three incident surfaces of a synthesizing prism, such as a green-light incident surface. Related art document Japanese Unexamined Patent Application Publication No. 11-38210 discloses another type in which the thickness of joining layers between rectangular prism elements included in a cross prism is varied in order to provide convex surfaces.